Thermostat regulating apparatus



July 14, 1936.

W. BT MACKI NTOSH THERMOSTAT REGULATING APPARATUS Filed Dec. 28, 195i atened July 14, 1936 THERMOSTAT PATENT OFFICE 2.047.878 REGULATING APPARATUS William B. Mackintosh, Knoxville, A'.lenn., aa-

signor to The ville, Tenn.,

Fulton Sylphon Company, Knoxa corporation of Delaware Application December 28, 1931, Serial No. 583,532

16 Claims.

This invention relates to a temperature regulating apparatus and more particularly to a temperature regulating apparatus for controlling the :dow of fuel to a consuming device.

It has heretofore been proposed to control the flow of fuel to a consuming device by means of a thermostatically operated valve, in which the motor of such thermostat is governed by the heat of a pilot name. However, in these constructions, when'the pilot flame becomes extinguished, the fuel can escape through the pilot burner, which may cause serious consequences when the pilot burner is relighted.

One of the objects of the present invention is to provide a novel device for regulating the ilow of fuel to a consuming device, which is governed by the temperature of a pilot flame and controlled by changes in temperature of the medium to be controlled such as ambient temperatures.

Another object of the present invention is to provide a novel device for regulating the ow of fuel to the main burner of a consuming device which is actuated by changes of temperature when subjected to the temperature of a pilot flame, but which shuts off the flow of fuel to both the main burner and pilot burner when the pilot flame becomes extinguished.

Another object of the present invention is to provide a novel device combining a control for the flow of fuel and a safety control for a pilot light which prevents the escape of the fuel when the pilot flame is extinguished, but which may be manually operated to supply fuel to the pilot burner for starting purposes.

Another object of the present invention is to provide a novel fuel controlling device which is simple and compact and efcient for the purpose intended.

These and other objects will become apparent from the accompanying description and drawing in which like reference characters denote like parts throughout the several views. It is to be expressly understood, however, that the drawing is for the purpose of illustration only and' not a definition of the limits of the invention, reference being had for this purpose tothe appended claims.

In the drawing,

Fig. 1 is a side elevational view in section of a fuel controlling device incorporating the present invention, the section being taken on lines I-I of Fig. 2;

' Fig. 2 is a cross-.sectional view through the device shown in Fig. 1, and taken on lines 2-2 of Fig. 1:

Fig. 3 is a side elevational view in section of the valve mechanism shown in Fig. 1, taken on lines 8 3 of Fis. 2.

The illustrated embodiment includes in its general organization a valve mechanism 4 for regulating the flow of fuel from a supply conduit 5 5 to a main burner of a consuming device (not shown) through outlet conduit 6, and to a pilot lburner l. The valve mechanism is actuated by a thermostatic motor 8, which is governed .by the pilot burner 1, and in case of failure of the pilot l burner to keep the motor hot. the valve will automatically close communication between the supply conduit and both the main and pilot burners. The motor 8 is controlled by a thermostat unit 9 which injects a fluid into the motor 15 upon increases in temperature and abstracts the fluid from the motor upon decreases in temperature of the medium to be controlled. However, the thermostat unit 9 is effective to control the motor only when the governing pilot burner has properly conditioned the motor 8.

The valve mechanism as shown includes a twopart casing I0 and II with the part Il forming a support for the motor 8. The casing I0 is of a generally cylindrical contour with an annular recess open at its upper side, and intersected by an apertured web I2 forming an annular valve seat I3. 'I'he casing part II is provided with an annular rib I4 adapted to t into the open side of the recess in the casing part I0 for closing the casing 30 and forming a second valve seat I4 vertically spaced from the valve seat I3. I'he two parts of the casing I0 and Il are Vmechanically heldin position by any suitable means such as bolts (not shown). A disk-like valve member I5 is positioned in the casing between the valve seats I3 and I4. 'I'he interior of the casing provides an admission chamber I 6 above the annular seat I4, a valve chamber Il between the annular seats I3 and I4 and an outlet chamber I8 below the annular seat I3. 'Ihe valve member I5 is of less .diameter than the interior of the casing I0 for allowing a ow of fuel to pass the valve when in an intermediate position, and is also-iimited in its movement by cooperation with one or the other of the valve seats I3 or I4.

On opposite sides, the casing part I0 is provided with any suitable means, such as internally threaded hollow bosses I9 and 20, for connection with the conduits 5 and 6 respectively. Communication is established between the inlet conduit 5 and the admission chamber I 8 by means of a passageway 2| formed in the casing member II, a wall 22 being provided between the hollow boss I9 and the interior of the casing. 65-

whilev the hollow boss 20 is in direct communication with the outlet chamber I9. On the periphery of the casing I0 intermediate the bosses I9 and 2li a third hollow boss 23 is provided, which directly communicates with the valve chamber I1. An outlet conduit 24 for the pilot burner 1 is connected to this boss 23 by any suitable means, illustrated as a compression coupling 25.

An actuating valve stem 26 is connected with the valve centrally thereof and extends from one side of the valve through an aperture in the casing member I I. 0n the other side of the valve a coil spring 21 is positioned between the valve I5 and the casing I I), normally tending to hold the valve against the annular seat I4, bosses 28 and 29 being provided on the valve and casing respectively, for properly vpositioning the spring. In the construction thus far described,l the valve I5 when held against the valve seat I4 by the spring 21 prevents the fuel, entering from the conduit 5 through the passageway 2I and .into the Aadmission chamber I6, fromentering the valve chamber I1, and the supply of fuel is cut off to both the main burner and auxiliary pilot burner. When the main valve engages the an nular seat i3 the fuel in the admission chamber I6 may enter the valve chamber I1 and supply the pilot burner 1 through-the conduit 24 but the fuel is shut off from the conduit 6 and the main burner. In'l any intermediate position of the valve I5 between the seats I3 and I4, fuel will be supplied to both the conduits 6 and 24 from the valve chamber.

For starting the apparatus in operation itis necessary to establish a communication between the admission chamber I6 and the conduit 24 to supply fuel to the pilot burner. To this end a bypass 3i)l is provided between the admission chamber I6 and the hollow boss 23, which is similar to the passageway 2l and is formed in the casing member II. This by-pass 30 terminates in a valve seat 3l and enters the hollow boss 23 which, as previously described, opens. into the conduit 24. This by-pass is held in a normally closed condition by a conical valve head 32 engaging the valve seat 3|. The valve 32 is held in position by a spring 33 engaging a recess in the casing vIl at one end, and the valve head 32 at the other end. A valve stem 34 connected with the valve head 32 extends outwardly through the casing I0 and at its outer end is provided with a handle 35 so that the valve 32 may be manu- ,ally actuated against the action of the spring 33 to open communication between the admission chamber I6 and theconduit 24 whenl the main valve I5 is held in engagement with the annular seat I4 by the spring 21.

The motor element Il for actuating the valve i5 includes an actuating member illustrated as a closed vessel having a rigid wall 35 enclosing a flexible bellows 31. The outer end of the bellows is connected to the rigid wall 361 by an intermediatecollar A38 while the inner end of the bellows is provided with a movable head 39, the wall and bellows being spaced by the collar 3B to form an expansion chamber therebetween. The valve stem 26 extending through the aperature in the casing part II is rigidly connected with the movable head 39 of the bellows so that movement of the head 39 is directly transmitted to the valve I5. A coil spring 40 surrounds thestem 26 for augmenting the action ofthe spring 21 and assisting in holding the bellows in its proper position.

The rigid casing 36 and collar 38 are connected any suitable means such as welding, and the casing 4I, in turn, is xed to and supported by the casing part II. The casings 36 and 4I are so shaped as to provide a heating chamber there- 5 between which entirely surrounds the operating element of the motor. Connected with this heating chamber, as by means of a conduit 42 welded to the side wall of the casing 4I, is a heating bulb 43 positioned in the path of the pilot burner flame and containing a vaporizable medium such as water adapted to transmit heat when vapor--y ized from the pilot ame to the motor element. In order to prevent the pressure in the heating chamber from becoming excessive, a condenser in the form of a tube 44 secured to the casing 4I and having a series of ns 45, is provided for transmitting heat to the surrounding atmosphere. In this manner heat is supplied to the heating medium at a constant rate and dissipated to the surrounding atmosphere at a predetermined rate depending upon the temperature differential between the two mediums, so that a desired temperature constant is maintained in the heating chamber. This desired temperature 25 is such that a thermosensitive fluid in the motor will be vaporized and actuate the bellows when the pilot flame is functioning properly but the thermosensitive fluid will not be vaporized if the pilot ame becomes extinguished. Although otherwise illustrated in the drawings for purposes of convenience, the conduit 42 and heating bulb 43 are preferably positioned below the lowest point in the heating chamber 4I so that the condensate of the heating medium will by gravity 35 ow back into the bulb.

The thermostatic unit 9 is connected by means of a tube 50 with the motor unit of the apparatus, the tube extending through casing 4I and casing 36, being secured to both to form a tight connec- 4( tion. I'he thermostat unit may be of any suitable construction but as shown comprises a base plate 5I adapted'to be attached to any suitable support, as by means of screws 52, kso as to be positioned in the medium to be controlled. 'I'his 4g b'ase plate 5I is centrally apertured as at 53 to receive a flexible bellows 54 having a movable head 56 and a stationary head 55, the latter being shown as provided with an apertured boss to receive the tube 59, which boss may also be ex- 51 tended to form a stop within the bellows. Be-

tween the stationary head 55 and the movable head 56 a coil spring 51 is provided for holding the bellows in a normally extended position.

This bellows is held in position within the aper- 5l ture 53 by means of a bar 58 pivot'ed'to the base 5I at one end and adapted to be swung into position under the stationary head 55, a slot 59 being provided in the bar to receive the boss on the head 55. 'I'his bellows is adapted to contain 6( the thermosensitive iluid which is injected into the motor unit 8 and when heated by the surrounding medium actuates the valve I5.

An actuating unit for the bellows 54 is adjustably mounted on a shoulder 60 of the base 6l ,omavs screw threads on the shoulder of the base. An abutment 65 extending from the movable head oi the bellows 33 is provided for engagement with the movable head 58 ofthe bellows I4. and is shown as formed by a tubular element'carrled by a boss on said head 66. T'his boss is centrally bored as at 65' for initially charging the unit with a thermosensitive duid which is effective within the temperature range to be controlled by the apparatus. After the initial charge has been placed in this chamber and sealed and the unit screwed to an adjusted position on the shoulder 60 of the base 5|, the abutment 63 acts as an actuating means for the bellows 63. The exact temperature at which it is desired to initially operate the apparatus may be predetermined by rotating the unit on the base 5I so as to require a greater or less expansion, as the case may be, of the bellows 62 before the abutment 65 engages the head 56 of the bellows 54.

The operation of the apparatus is as follows:- As a starting condition let it be assumed that neither the main burner nor the pilot burner are lighted, that the heating chamber is cold, and the medium whose temperature is to be controlled is cold, at which time the valve I5 will be seated against the annular valve seat I4 by the spring 21 vand communication between the admission chamber I6 and both of the outlet conduits 6 and 24 entirely shut oi. The apparatus is then started in its operation by manual actuation of the valve head 32 by means of the handle 35 and against the action of the spring 33, allowing a communication between the admission chamber I6 and conduit 24 leading to the pilot burner through the by-passV 3U, and the fuel is ignited at the burner 1. This pilot burner 1 is adjacent the main burner and also in position to heat the bulb 43. As soon as the bulb 43 is heated. the heating medium within the bulb will be vaporized and ilow through the .cpnduit 42 into the heating chamber between the casing 36 and 4I causing a small residual charge of the less volatile thermosensitive iuid in the motor chamber 8 to be vaporized and to move the valve I5 to the position shown in Fig. 1. 'Ihe fuel then flows from the conduit 5 through the admission chamber I6, valve chamber I1, between the exterior diameter of the valve I5 and the interior diameter of the casing 4 to the outlet chamber I3, and then through the conduit 6 to the main burner which will immediately be ignited by the pilot burner 1. The manually operated valve.32rmay then be released, and by the spring 33, will close communicati'on between the by-pass 30 from the admission chamber, I6 to the conduit 24, and the fuel will then be supplied to the pilot burner from the valve chamber I 1 and through the outlet connection 23 to the conduit 24. As the main burner increases the temperature of the medium to be controlled, the thermostatic unit 3 will be actuated. Temperature increases acting on the thermostat 9 will cause the head 63 to be moved to the left as shown in Fig. 1 until such time as the abutment 65 engages the head 56 of the bellows 54 and forces a small quantity of the volatile thermosensitive fluid contained therein through the tube 50 and into the motor chamber of the motor 8. The heat of the chamber surrounding the motor chamber immediately vaporizes the thermosensitive iluid and causes the movable head 39 to act against the tension of the springs 21 and 40 to move the valve I 5 toward the annular valve seat I3 and throttle the ilow of fuel to the main burner.l If the temperature of the medium to be controlled continues to increase more vof the volatile thermosensitive fluid will be forced into the motor chamber and the valve I6' will be moved in accordance therewith; until it is nnally seated on the annular valve seat I3 shutting olf tialvacuum in the tube 50 and chamber of the motor 8 so that part of the thermosensitive uid in the chamber will be moved back toward the bellows 54 and become condensed, until such time as the valve I5 again opens and allows the fuel to flow to the main burner to be immediately ignited by the pilot burner 1. However. if the pilot burner becomes extinguished, the condenser quickly dissipates the heat in the heating chamber, and the thermosensitive iluid in the motor chamber 8 condenses, allowing the springs 21 and 40 to move the valve I5 against the annular valve seat I4, to shut off all communication between the admission chamber I6 and both the main burner and pilot burner, preventing any llability of damage by explosion caused by leakage and accumulation of fuel from the pilot burner 1.

The motor is maintained in an operative condition to be actuated by changes in temperature of the ambient, as long as the pilot burner remains ignited, and becomes inoperative when the pilot burner becomes extinguished. but in order to prevent excessive pressure in the chamber between the casings 36 and 4I, and to maintain the actuating element of the motor at a substantially constant operating condition, the condenser is provided. The radiating surface 45 of the condenser is such that it will dissipate heat at a rate proportionate to the heat transmitted to the motor. In this manner the motor is maintained at a substantially constant operating condition which prevents any changing temperature condition of the motor which might aiiect the proper operation of the thermostat.

It will now be apparent that an eiiicient, simple and compact apparatus has been provided for controlling the flow of a fuel to a main burner, which is actuated in accordance with the temperature of the medium to be controlled only when the pilot burner is lighted. It Will be further apparent that the apparatus combines such a controlling device with safety features that prevent the escape of the fuel when the pilot flame is extinguished and liability of dangerous consequences.

It will also be apparent to those skilled in the art that various changes may be made in the size, shape and details of construction without departing from the spirit of the present invention. Any other suitable type of thermostat, heating means for the motor chamber, condenser or connecting means may be used in place of those described, and in some cases the condenser may be entirely eliminated, without departing from the spirit of the invention. It will alsobe perceived that the invention may be embodied in devices for controlling the temperature of a variety of mediums and that the thermostat may be subjected to liquid as well as to gaseous mediums the temperatures of which are to be controlled. The embodiment disclosed and illustrated in the drawings does not, therefore, de-

1. In av fuel control device, an expansible'andv contractible motor for varying the flow of fuel to a main burner, an auxiliary burner governing the' operation of the motor, a thermostat for controlling the motor when put in an operative condition by the governing means. and means for stopping the ow of fuel to both the main and auxiliary burners when the flame of the auxiliary burner is extinguished.

2. In a fuel control device, a valve, an expansible and contractible motor i for actuating the valve and varying the flow of fuel to a main burner, an auxiliary burner governing the operation of the motor, a thermostat for controlling -the motor when put into an operative condition by the governing means, means for closing the valve and stopping the flow of fuel to both the main and auxiliary burners when the ame of the auxiliary burner is extinguished, and a manually controlled by-pass for supplying the auxiliary burner with fuel when the valve is closed.

3. In a fuel control device for a heating apparatus having a main` and a pilot burner, a valve for controlling the ow of fuel, means for normally actuating the valve to vary the iiow of fuel to the main burner in accordance with the temperature of the medium to be controlled, said means including a motor element operated by fluid pressure, means for rendering said motor element capable of generating an effective vapor pressure only when said pilot burner is ignited, and a second means for actuating the valve to a position to stop the flow of fuel to both the main and pilot burners when the name of the pilot burner is extinguished.

4. In a fuel control device, an expansible and contractible motor for varying the ow of fuel to a main burner, a chamber surrounding the motor, an auxiliary burner for heating the chamber and governing the motor, a thermostat for controlling the motor when heated by the auxiliary burner and chamber, and means for stopping the flow of fuel to both the main and auxiliary burners when the flame of the` auxiliary burner is extinguished. l

5. In a fuel control device, an expansible and contractible motor for varying the ow of fuel to a main burner, a chamber surrounding the motor, an auxiliary burner adjacent the main burner, a bulb containing a uid positioned in the flame of the auxiliary burner, a conduit connecting the bulb and chamber for transmitting heat from the auxiliary burner to the chamber and governing the operation of the motor a thermostat for controlling the motor when heated by the auxiliary burner, and means for stopping the flow of fuelto both the main and auxiliary burners when the flame of the auxiliary burner is extinguished.

6. In a fuel control device, a main burner, an auxiliary burner, an expansible and contractible motor for stopping the flow of fuel to the main burner in one extreme position and to both the main and auxiliary burner in another extreme position but varying the flow of fuel to the main burner in intermediate positions, means for governing the operation of the motor in accordance with the condition of the auxiliary burner, a thermostat for controlling the motor to vary or stop the flow of fuel.to the main burner when put in an operative condition by the governing means, and means for actuating the motor to stop the flow of fuel to both the main and auxiliary burners when the name of the auxiliary burner is extinguished- A 7. In a fuel control device. Amechanism for` varying the flow of fuel to a main burner, a 6 chamber surrounding the mechanism. an 'auxiliary burner for heating the chamber, a thermostat for controlling the mechanism when the chamber is heated by the auxiliary burner, and means for stopping the flow of fuel when the flame of the auxiliary burner is extinguished.

8. In a fuel control device for a heating apparatus having a main and a pilot burner, valve mechanism for stopping the flow of fuel to the main burner in one extreme position and to both l5 the main and pilot burners in another extreme position but varying the flow of fuel to the main burner in intermediate positions, a thermostat including a motor vessel adapted to be actuated by vapor pressure for normally actuating the 20 valve mechanism to vary or stop the flow of fuel to the main burner in accordance with the temperature of the medium to be controlled, heating means for rendering said motor vessel capable of generating a vapor pressure to actuate said 25 valve mechanism only when said pilot burner is ignited, and mechanism to actuate the valve mechanism to a position to stop the flow of fuel to both the main and pilot burners when the flame of the pilot burner is extinguished.

9. In a fuel control device, a valve, an expansible and contractible vessel for actuating the valve, an auxiliary burner for heating the vessel, means actuated by anincrease in temperature for injecting a quantity of thermosensitive iiuid into the vessel, said vessel when heated by the auxiliary burner controlling the flow of fuel to the main burner, and means for stopping the flow of fuel when the flame of the auxiliary burner is extinguished.

10. Inl a fuel control device, a main burner, an auxiliary burner, a valve operable in one extreme o position to stop the ilow of fuel to both the mainand auxiliary burners and in another extreme position to stop the flow of fuel to the main burner only, a hot vessel for actuating the valve, means for transmitting heat from the auxiliary burner to the vessel and governing the operation of the valve, means actuated by an increase in temperature for controlling the operation of the valve from one extreme position to the other, and means for moving the valve to cut off the flow of fuel to both the main and auxiliary burners when the flame of the auxiliary burner is extinguished.

11. In a fuel lcontrol device. a casing having inlet and outlet sides with a valve seat between. a main burner and an auxiliary burner connected to the outlet side of said casing, a valve cooperating with the valve seat, a closed vessel having a 50 movable wall connected to the valve, a heating means surrounding the vessel and subjected to the temperature of ythe auxiliary burner, and means actuated by increases in temperature for injecting small quantities of a liquid thermo- 65 sensitive uid into theV hot vessel.

12. In a fuel control device, a casing having an inlet chamber, an outlet chamber and an intermediate valve chamber, a pair of spaced valve vseats in the valve chamber, a valve cooperating 70 vessel with a heated medium and subjected to the heat of the auxiliary burner, and means actuated by increases in temperature for injecting small quantities of a liquid thermosensitive uid into the hot vessel whereby said liquid when vaporized will move the movable wall and actuate the valve.

i3. In a fuel control device, a thermostat for varying the iiow of fuel to a main burner including a bellows, a heating jacket surrounding the bellows and containing a heat transmitting medium, an auxiliary burner for heating the bellows through the heat transmitting medium, means for dissipating the heat in the medium at a substantially constant rate so that the temperature of the bellows may be maintained substantialiy constant, means subjected to the temperature variations for injecting a thermosensitive iluid into the hot bellows upon a temperature increase, and means for discontinuing the ilow of fuel to both the main and auxiliary burners when the ame of the auxiliary burner is extinguished.

14. In a fuel control device, a valve for controlling the fuel ow, a motor for operating said valve, a heating chamber surrounding said motor, a thermostat for developing pressure in said motor when said motor is hot, an auxiliary burner, and heating means subjected to said auxiliary burner and communicating with said heating chamber for rendering said motor operative.

15. In a fuel control device. a valve, a motor for operating said valve, a thermostat for injecting a vaporizable liquid into said motor upon changes of temperature, a chamber for heating said motor to render said thermostat effective to actuate said valve, and means including a container for a heating medium subjected to a ame maintained by said fuel and communicating with said chamber to heat said chamber and render said motor operative.

16. In a controlling device for a heating medium, a valve for controlling the ow of heating medium, an expansible and contractible motor vessel operatively connected to said. valve, a

heating chamber surrounding said motor vessel,

thermostatic means for injecting a vaporizable liquid into said motor vessel. means for heating Said heating chamber,. and means i'or closing said valve when the temperature of said heating chamber is insuiiicient to vaporize said liquid in said motor vessel.

WILLIAM B. MACKINTOSH. 

